CyberSecBulletin
CVE-2024-20094NVD status: Analyzed

MT2735, MT6833, MT6853, MT6855, MT6873…: Reachable Assertion

Published Updated By the CyberSecBulletin desk

CVE-2024-20094 is a high-severity reachable assertion vulnerability in MT2735, MT6833, MT6853, MT6855, MT6873, MT6875, MT6875T, MT6877, MT6880, MT6883, MT6885, MT6889, MT6890, MT6891, MT6893, MT8675, MT8771, MT8791, MT8791T, MT8797 from MediaTek, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected MT2735, MT6833, MT6853, MT6855, MT6873, MT6875, MT6875T, MT6877, MT6880, MT6883, MT6885, MT6889, MT6890, MT6891, MT6893, MT8675, MT8771, MT8791, MT8791T, MT8797 versions: Modem NR15. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.75% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of MT2735, MT6833, MT6853, MT6855, MT6873, MT6875, MT6875T, MT6877, MT6880, MT6883, MT6885, MT6889, MT6890, MT6891, MT6893, MT8675, MT8771, MT8791, MT8791T, MT8797 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on corp.mediatek.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MediaTekMT2735, MT6833, MT6853, MT6855, MT6873, MT6875, MT6875T, MT6877, MT6880, MT6883, MT6885, MT6889, MT6890, MT6891, MT6893, MT8675, MT8771, MT8791, MT8791T, MT8797Modem NR15Not stated
MediaTekmt2735all versionsNot stated
MediaTekmt6833all versionsNot stated
MediaTekmt6853all versionsNot stated
MediaTekmt6855all versionsNot stated
MediaTekmt6873all versionsNot stated
MediaTekmt6875all versionsNot stated
MediaTekmt6875tall versionsNot stated
MediaTekmt6877all versionsNot stated
MediaTekmt6880all versionsNot stated
MediaTekmt6883all versionsNot stated
MediaTekmt6885all versionsNot stated
MediaTekmt6889all versionsNot stated
MediaTekmt6890all versionsNot stated
MediaTekmt6891all versionsNot stated
MediaTekmt6893all versionsNot stated
MediaTekmt8675all versionsNot stated
MediaTekmt8771all versionsNot stated
MediaTekmt8791all versionsNot stated
MediaTekmt8791tall versionsNot stated
MediaTekmt8797all versionsNot stated
MediaTekNr15Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CISA (ADP).

Official description

In Modem, there is a possible system crash due to a missing bounds check. This could lead to remote denial of service with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY00843282; Issue ID: MSV-1535.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Reachable Assertion

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How developers prevent this class of flaw

  • If the assertion statement is required (e.g., for security or reliability), change the invoking code to avoid the conditions that trigger the assertion.
  • Consider changing the assertion to some other less fatal error. This might not be easy to implement, since other code may be needed to handle the error.
  • Make sensitive open/close operations non-reachable from directly user-controlled data (e.g. open/close resources)

More Reachable Assertion vulnerabilities (CWE-617)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Reachable Assertion vulnerabilities

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